ABC (programming language)

ABC is an imperative general-purpose programming language and integrated development environment (IDE) developed at Centrum Wiskunde & Informatica (CWI), in Amsterdam, Netherlands by Leo Geurts, Lambert Meertens, and Steven Pemberton. It is interactive, structured, high-level, and intended to be used instead of BASIC, Pascal, or AWK. It is intended for teaching or prototyping, but not as a systems-programming language. ABC was developed from the B language, an earlier creation by Meertens and Pemberton (unrelated to Thompson and Ritchie's language of the same name) which was the first language to use indentation for block structure. ABC had a major influence on the design of the Python language, whose creator, Guido van Rossum, had worked for several years on the ABC system in the mid-1980s. Its designers claim that ABC programs are typically around a quarter the size of the equivalent Pascal or C programs, and more readable. Key features include: ABC was originally a monolithic implementation, leading to an inability to adapt to new requirements, such as creating a graphical user interface (GUI). ABC could not directly access the underlying file system and operating system. The full ABC system includes a programming environment with a structure editor (syntax-directed editor), suggestions, static variables (persistent), and multiple workspaces, and is available as an interpreter–compiler. As of 2020, the latest version is 1.05.02, for Unix, MS-DOS, Atari ST, and MacOS.